A great taming bug for these guys is to let them wake up, set your starve timer and let the narcs run out on them, then, when the timer is almost up, ko them again and drop the kibble in, saves you tons of narcotics
for those who aren’t sure, beavers spawn in asgard! i found a few at lat-32.7 lon-26.3 (in asgard) also, if you are not sure on how to get to asgard, there is a small cave at lat- 39.8, lon-57.9 with portals to all 3 sections in. hope this helps!
I play on singleplayer, make sure the one you wanna tame is alone and doesn't have it's buddies arouns, bola it and knock it out usinf tranq arrows, took around 100 mejorberries and 20 narcotics. Time? Around 20-30 minutes.